The polarizer quads were also designed to map onto a four-faceted WFC configuration and, consequently, also require a partial filter rotation of -33° to move the filter quadrant 1 (nominal polarization angle 135°) into WFCs 2 and 3, with some vignetting of both camera fields. Several additional partial rotations have been added to allow observations with different polarization angles on the same CCD. ... Table 3.10: Polarizer Quad Filter. ... Filter Name . ... Nominal filter wheel position . ...

... NICS will be the only infrared instrument for the first light of the TNG; as a consequence, we decided to incorporate a sufficient degree of operation flexibility by providing the instrument with six different observing modes, three aimed at imaging and three at spectroscopy: . ... It will be possible to use the narrow band filters as order sorters; this will allow to perform high resolution long-slit spectroscopy in the wavelength ranges covered by the available narrow band filters. ...

Next: OTHER DIGITAL BACKENDS: Up: Wide Band Observing: RDBE, Previous: The RDBE system Contents . The DBBC being developed for the EVN and many geodesy stations is also a system that samples at 512 or 1024 MHz and digitally filters the signals to the desired bandwidths. ... Support for the DDC personality of the DBBC has recently been implemented in SCHED, but should be used with caution. ... The frequencies for the band edges in the DDC personality can be set to any multiple of 10 kHz. ...

... Exposure Time Calculator (ETC) . ... ESO - Public Surveys . ... the recommended values to use for DIT, . ... Detector on-chip integration (DIT): seconds. to your chosen value - a separate page gives recommended values to use for DIT - for modes 1 and 2 below you may wish to start with the maximum recommended values as these will minimize the effect of read noise (a total object exposure of Y secs with DIT=X secs will produce Y/X lots of read noise) and give you a lower limit on the time needed. ...

... Tonight's Sky . ... Observing . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... solar system . galaxies . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Imaging Basics . ... Observing Basics . ... Observing Basics: Visual Solar Filters . ... Expand your observing at Astronomy.com . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... Meade Series 4000 Nebular Filters incorporate the very latest in interference coatings technology. ... Technical Basis of the Meade Broadband Nebular Filter: As shown in the transmission graph below, the Meade Broadband Nebular Filter strongly rejects the light of sodium- and mercury-vapor lights as well as natural airglow and auroral emissions. ... Meade Series 4000 Narrowband Nebular Filters . ... Meade Series 4000 Oxygen-III Nebular Filters . ... Meade Series 4000 Photo-Visual Color Filters . ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

Next: Reducing the observations Up: PEPSYS general photometry Previous: Influencing the plan . ... If the telescope and instrumentation are unfamiliar to you, you may have trouble keeping to the schedule for the first night or two, so try to work with a previous observer on the equipment for a night or two of training before your observing run. If you fall behind, try to keep as many low-altitude observations of extinction stars as you can, and drop some circumzenithal ones if necessary. ...